Type II sensory fiber (group Aβ) is a type of sensory fiber, the second of the two main groups of stretch receptors. They are non-adapting, meaning that even when there is no change in muscle length, they keep responding to stimuli. In the body, Type II fibers are the second most highly myelinated fibers.
The muscle's instantaneous length, or position,is directly proportional to their firing rate. This information would indicate the position of one's leg once it has stopped moving. They do not respond to rate of length changes as do the Ia fibers.
Type II fibers connect to nuclear chain fibers, but not to nuclear bag fibers. These connections, referred to as "flower spray endings" due to their appearance, embed into the poles (ends) of the fibre. It is thought that the relative position of the equatorial regions of the spray when stretched determines the action potential output.
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Famous quotes containing the words type, sensory and/or fiber:
“Chicago—is—oh well a façade of skyscrapers facing a lake, and behind the façade every type of dubiousness.”
—E.M. (Edward Morgan)
“Our talk of external things, our very notion of things, is just a conceptual apparatus that helps us to foresee and control the triggerings of our sensory receptors in the light of previous triggering of our sensory receptors.”
—Willard Van Orman Quine (b. 1908)
“I am an invisible man.... I am a man of substance, of flesh and bone, fiber and liquids—and I might even be said to possess a mind. I am invisible, understand, simply because people refuse to see me.”
—Ralph Ellison (b. 1914)